Output characteristics of an X-ray laser based on the GRIP geometry are analysed by both the theoretical and experimental methods. Detailed analysis of the last experiments on GRIP X-ray lasers with a single profiled pulse is given as well as the consequences of this pump variant for the injector-amplifier scheme being developed. Especially dynamics of the gain coefficient and the spontanous emission flux are important for the injector-amplifier scheme. Discussion on medium dynamics and kinetics is supported by numerical simulations. Additionally, some preliminary results on seeding a
Ni-like soft X-ray with high harmonic from neon at 13.9 nm are presented.
The wavefront aberrations in the 100 TW laser pulses are measured and corrected to improve the intensity distribution of
the focal spot. Before correcting wavefront aberration of the laser pulses, the laser pulses have higher-order aberrations
such as coma, trefoil, and spherical aberration as well as defocus and astigmatism. The wavefront aberrations in the laser
pulses are corrected by the deformable mirror. The dynamic and static corrections are tested with the deformable mirror.
When correcting wavefront aberrations with the deformable mirror, the focal spot having a 1.2 times spot size of the
diffraction-limited focal spot is observed.